For all the talk about how dark Harry Potter and the Half-Blood Prince is, the mega-hit still has a PG rating. In fact, it was probably a few drops of blood and a kiss or three away from attaining a G rating. This summer, audiences don’t appear to be discriminating much either between PG flicks and the PG-13 movies with their slight increase of sex and violence. But if you had to pick one over the other, which would it be? PG films like Harry Potter and Up or PG-13 hit like Transformers and Star Trek? Just how grown up are you?